Method of and machine for straightening bars



INVENTOR Hm mi N m uw@ mw m m G. A. KEENAN.

METHOD 0F AND MACHNE FORl STRAIGHTENING 'B'RS.

lAPPLICATION FILED JULY 2, |920- lQ, Patented Nov 1,1921

3 SHEETS-SHEETI G. Ax KEENAN.

METHOD 0F AND NIACHNE FOR STRAIGHTENING BARS.

.APPLICATIGN FILED JULY 2; i929.

mente@ Nov. 1, 1.921.,

3 SHEETS-SHEET 2.

G. A. KEENAN.

METHOD 0F AND MACHINE FOR STRAIGHTENING BARS.

APPLICATION FILED .IULY 2,1920- Patentdllov. 1, 1921.

3 SHEETS-SHEET 3.

. lvm

I 4 `/J. INVENTOR ma, 5 /LL7J WW'NESSES GEORGEV A. KEENAN, OF PTTSBURGH, FENNSYLVANIA.

METHOD OF AND MACHINE FOR STRAIGHTENING B'ARS.

To all whom it may concern.'

Be it known that I, GEORGE A. KEENAN, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful lmprovements in Methods of and Machin-es for Straightening Bars, of which improvements the following is a specification. n

My invention relates to improvements 1n methods of and machines for straightening bars, and more particularly for straightening rolled steel bars, such as are nowadays produced in considerable quantities to meet the demands of automobile manufacturers, of manufacturers of screws and bolts, and elsewhere in the industrial arts.

In the accompanying drawings amachine is illustrated` in'which and in the operation of which my invention may be realized. Figure I is a plan view of the driving mechanism of the machine; Fig. H is a' view in elevation as seen on the lines indicated at II--II Fig. HI, and with the omission of the driving mechanism; Fig. HI is a view in end elevation and to larger scale; Figs. IV and V are views in vertical section and to larger scale, on the planes indicated by the lines IV-IV and V-V, Fig. Il; Fig. VI is a diagrammatic view,` to illustrate modi/s operandi.

Heretofore, in the production of articles of the character'indicated, it has been the practice to pass a bar between a succession `of rolls so arranged as to throw the bar into a succession of waves; then in like manner Ato impose upon the bai' a waved configuration, in a plane at right angles to the first set of waves; and then, in successive rolling operations, to reduce and eliininate the two sets of undulations. This somewhat blind statement will be made clearer on consideration of the diagrammatic view, Fig. VI. Here appears a succession of rolls, 1, Q, i3, il, and 5,'arranged with their parallel axes in two parallel planes, and on either side of a mid line a-b. The successive rolls in the two parallel rows are staggered in their relativ-e positions and they overlap the mid line, as shown. The effectand consequence is that a har fed between is thrown into undulated shape and. the undulations exceeding the elastic limit of the material, the undulated Specification of Letters Patent.

Patented Nov. 1, 1921.

`i9tpip1iea-tion iled July 2, 1920. Serial No. 393,521.

shape is, so far as this step of the operation As a bar passes from this set of rolls it is brought through a. second and similar set, in which undiilation in a plane at right angles to the plane of the first undulation is imposed upon it. Subsequently, the operations being repeated, but with diminished range of deflection, the undulations first imposed are ironed out and the bar brought to substantial straightness. The Weaving of the metal involved in the operation takes out such kinks and irregularitiesl as the bar initially possessed.

In the performance of this operation as heretofore conducted, it has been necessaryv either to provide a plurality of the double roll sets (one for each degree of waving) or else to operate upon rods batch by batch, and run one batch repeatedly through the same mill, stopping between the repetitions to alter the positions of the rolls. ln the one case there is multiplication of machinery and occupation of large floor space, as well as (when compared with the conditions of my improved operation) a relatively large consumption of time; in the other case, the loss lof time is a still more pronounced'disadvantageous factor.

The method heretofore employed, it will be perceived. is (l) to throw the rod into undulations in one plane, (2) to throw it into uiidiilations in a second plane. to

reduce the height of the undulations in one plane, (4) to reduce the height of the undulatioiis in the second plaiie-aiid so to continue, so far as may be necessary. Usually there are three or four repetitive passes. So much for the old operation. My improved method is (l) to throw the iod into undulations in one plane and then in continuous operation, between rolls of diminished overlap, to iron out" those first undulations, then (2) to repeat the same operation in the other plane. And -with these two steps the operation is completed.

Referring again to the drawings, and particularl)v to Fig. II, two sets of rolls are shown; and these two sets` seen in this figure at" different angles. are it will be understood duplicates. One set operates on the material to raise and then to reduce again undulations `in.one plane. the other to raise and reduce again undulations` in another plane, and these two planes of undulation at b.

are at right angles one to another: Accordingly, the two sets as shown in Fig. II present a diverse appearance. The conveyer 6 carries the bars under operation from one set of rolls to the other.

Confining attention to the .rolls of one set, they are arranged with their parallel axes in two parallel planes or, with the minutiae presently to be described, substantially so. As seen on the left in Fig. II, the set is in this instance made up of thirteen rolls, numbered T to 19, and this is an adequate numy ber. Cooperating with the first roll of the series, to drive forward an introduced bar, is a pinch roll 20. The direction of advance of the bar is from left to right, as indicated by an arrow. rI`he rolls of one of the two rows of which each set consists (conveniently the lower row, 7,9, 11-19), are positively driven; the .rolls of the other row, the upper, (8, 10, 12-18) turn idly. Means for rotating the rolls of the lower rows of the two sets will be found in a motor 21, two driven shafts 22 and 23, and beveledgear connections from the shafts to the rolls themselves. The upper idly turning rolls are adjustable individually in vertical direction by means of hand wheels 24:. By the positioning of these rolls the amount of flexure imposed on the passing bar is deter-` mined. The rolls of either or both rows are essentially plain-faced, though they may be grooved, to more certainly retain and guide the passing material. The machine as shown in the drawing is designed to operate upon square bars, and in this case it is convenient and advantageous to have the rolls of the upper row,.the idly turning rolls 8, 10, 12, etc., plain-faced, and the rolls of the lower and positively driven row. T, 9, 11, etc., grooved to proper shape and -proportion to receive the bar to be treated. See in this connection Figs. IV and V, where, in Fig. IV, a bar under treatment is indicated The rolls of both rows might be grooved. w a..

The first bend or undulation in an infed bar is formed by rolls-T,v 8. and 9, and the undulation is reversed as the bar meets each succeeding roll, 10, 11, 12, etc.

The rolls are so set, preliiniiiarily, that, in the forming of the first undulation, the elastic limit of the material is exceeded. If the machine were stopped, the rolls separated, and the bar removed, it would be found that the undulation at that point would remain. What the actual degree of overlapping of the rolls upon the middle line a-b (cf Fig. VI) will be, must depend on the size of the bar and t-he quality of the material; ordi? narily, it will amount to an eighth of an inch ormore. The succeeding rolls, 10, 11, 12, etc., are so set that the undulation first iinposed between rolls 7, 8, and 9 is gradually diminished, until, as the bar passes out beneath roll 18 and over roll 19, novundulation is left, but, the bar in that planeA of de I flection is straight. i

Pa sing to the second set of rolls, the rightliand set as seen in Fig.` II, the bar is subjected to similar instrumentalities set in similar manner, and undergoes similar treatment, but all in a plane at right angles to that of the initial operation. Being thus rptiied in two planes the bar is rectified in The number of rollsrequsite to make up a set which shall achieve the end described, is not susceptible of precise definition.; for it will vary, accordingas the material 4to be treated varies. The set of 4 thirteen rolls shown I have found to be adequate to vdeal with steel' bars ranging inthickness from half an inch to an inch and eleven sixteenths. I do not, however, limit myself to this number, either as maximum or minimum, but

mean to include operations performed by.

and between a greater number of rolls and between a smaller number as well,` the only requisite being that the esssential features of treatment which -I describe, be achieved. l have found as a matter of practice however that at least three double undulations, and by double undulation I mean a wave made up both of crest and trough, are necessary in order to effect my ends.

When the machine is once set and the adjustments in position of the successive'rolls once made, it will operate on a continuous succession of bars fed into it one by one and will, so far as roll adjustment is concerned, operate indefinitely. Operation of the old machines alluded to above is limited and embarrassed and delayed by the necessity for repeated adjustments inv roll positions, to meet even the necessities of o erating on a chance bar of more than or inary irregularity. Besides this, as has been said, the machine which achieves my improved method is notable in producing a bar fullyr straightened in a single passage through. yIn the old machine it is necessary to make repeated passes, with manifest delay anzd disadvantage.

Not 'onl is my invention, so far as concerns met od, free of limitation in respect to the number of rolls, or equivalent shaping instrumentalities, employed; it is not limited to any other of the particular mechanical instrumentalities shown. These are shown by way of example merely.r

I claim as my"-l invention: f p

1. The method herein described of straightening a metal bar which consists in submitting the bar while'otherwise free of longitudinal tension to a succession of three double undulations of gradually diminishing amplitude and causing such undulations to traverse the bar from end to end in one plane, and then repeating the operation in QSI..

-subjecting the bar while'otherw'ise a plane transverse to the plane of the first operation.

2. The method herein described of straightening a metal bar'which consists in longitudinal tension to the weaving action of a succession of staggered rolls, whereby a succession of three double undulations of diminishing amplitude is caused to traverse the bar from end to end, the first undulation being of a magnitude exceeding the elastic limit of the material, and then subjecting the bar to a repetition of the operation in a plane transverse to that of the rst operation. y

3. In a machine for straightening metal bars the combination of two sets of rolls, the

rolls of each set standing parallel roll to roll, and the rolls of one set standing at right angles to the rolls of the other set, each set consisting of six rolls arranged in staggered succession on opposite sides of the line of draft between, all of the rolls on one side of the line of draft in each set being positively driven from a common source'of free of power, and each of the rolls on the other side of the line of draft in each set being separately adjustable transversely of the line of draft.

4. In a machine for straightening metal bars, the combination of two sets of rolls, the rolls of each set arranged in staggered succession on opposite sides of the line of draft and the rolls of one set extending at right angles to the rolls of the other set, all the rolls on one side of the line of draft in each set being grooved, and all the rolls on the other side of the line of draft of each set being plain faced, all' of the rolls on one side of the line of draft in each set being power driven and each of the rolls on opposite sides of the line of draft of each set being individually adjustable in a line transversely of the line of draft.

In testimony whereof I have hereunto set my hand.

GEORGE A. KEENAN. Witnesses:

BAYARD H. CHRISTY,

FRANCIS J. ToMAssoN. 

